Hi! I Have 4 ylxd41yl and 2 ylxd42yl Yeelight Ceiling lights in HomeKit. Sometimes it lose connection with HomeKit, but it actually works in Yeelight/MiHome app.
ylxd41yl firmware 2.0.6_0021
ylxd42yl firmware 2.0.6_0023
mi id 1594452186
Also in MiHome app -> Network info see “Poor connection”. But Wi-Fi router is in same room with distance less then 5m